Two conflicting positions in the literature regarding changes in adult learning and memory with age make quite different predictions. One, the deficit hypothesis, predicts that primarily quantitative differences will occur; whereas the other, difference hypothesis, predicts qualitative differences between young and older adults resulting from the responses of qualitatively different processing systems. Most studies of learning and memory in older adults have been designed to test only the deficit hypothesis, investigating single variables. The present studies are designed to contrast the difference and deficit hypotheses. Rather than minipulating individual variables, these studies vary different types of variables simultaneously to compare patterns of performance across several different learning environments. Two sets of studies are proposed to investigate linguistic integration processes. Linguistic integration is of particular adaptive importance for older adults and differential predictions can be made for different age groups. All studies involve at least one factor that is expected to vary in ecological relevance for older adults. In some cases, the materials vary in their relevance to specific age and occupational specialization groups. Other factors include motivation enhancement and learning conditions and measures consistent with learning experiences of older adults. Variables are contrasted in naturalistic settings, laboratory settings, or both. In all cases, procedures are developed to compare and contrast the deficit and difference hypotheses in complex learning environments varying in ecological relevance for young and older age groups.